React js axios在邮递员中工作时出现CORS错误

Question

In my Mern Stack Project I am facing a problem when I am creating a Lesson from postman its created successfully but when I am trying from my browser its given me 500 error in network tab. But in console i got CORS error and also 500 error. I am including SS in bellow if anyone can face this kind of problem please help me. I am trying all the similiar solution from stackoverflow.

Access to XMLHttpRequest at 'https://lms-api-v1.coderslab.com.bd/api/v1/lesson/add' from origin 'http://localhost:3000' has been blocked by CORS policy: No 'Access-Control-Allow-Origin' header is present on the requested resource.

 const apiClient = axios.create({ baseURL: "https://my-link", withCredentials: false, accesscontrolalloworigin: "*", accesscontrolallowMethods: "GET, POST, PUT, DELETE, PATCH, OPTIONS", }); // Create Lesson export const createLesson = (lessonData, token) => async (dispatch) => { try { dispatch({ type: NEW_LESSON_REQUEST }); const config = { headers: { Authorization: `Bearer ${token}`, 'Access-Control-Allow-Origin' : '*', 'Access-Control-Allow-Credentials':true, 'Access-Control-Allow-Methods':'GET,PUT,POST,DELETE,PATCH,OPTIONS', }, }; const { data } = await apiClient.post(`lesson/add`, lessonData, config); dispatch({ type: NEW_LESSON_SUCCESS, payload: data, }); } catch (error) { dispatch({ type: NEW_LESSON_FAIL, payload: error.response, }); } };

Answer 1

you need to allow origin from backend. like this

Access-Control-Allow-Origin: http://localhost:3000

Answer 2

在后端添加这个

Access-Control-Allow-Origin: '*'